Machine for turning regular hexagons.



N0. fi33,|08. Patented Sept. l2, I899.

W. B. PEARSON.

MAQHINE F08 TURNING REGULAR HEXAGUHS.

A iiminn an 13.2.4, 1898.)

{No Medal.) I 2 SheetsShBBt I.

III IIEII T 00 WITNESSES nromvsy.

will? @213; .Pmrsorg No. 633,l08. Patented Sept. l2, I899.

W. B. PEARSON. IAGHINE FOR TURNING REGULAR HEXAGRNS.

2 sheets sheet 4 UNITED 4 STATES PATENT OFFICE.

WALTER B; PEARSON, OF CHICAGO, ILLINOIS.

SPECIFICATION forming part of Letters Patent No. 633,108, dated September 12, 1899. I

Application filed January 4.1898. Serial No. 665,569. "No morlel-l lie it known that I, Waursn l3. lnausos, a citizen of the United States, and resident of (,hicage, in the county of Cook and State 5 of Illinois, have invented an Improved 'lool or Mechanism for (letting or Turning Regular Ilexagons, ol" which the following is .aspecification. v i I This invention relates to an improved tool or mechanism for cutting or turning regular hexagon-s, and relates particularly to an improved tool or mechanism for this purpose of the general type, comprising a rotary cutter supported cceentricallyto the center of 'the work or polygon to be cut,'to which rotary movement relatively to the work is imparted either by revolving the cutter about the work or by rcvolvinglhc work upon its own ails or otherwise.

My ultimate object has been-to provide a tool or mechanism of this general type in which the cutter hasa uniform angular velocity both upon its own axis and also rela" tively to the work and which will cuta regular hexagonal figure or shape the sides of which are forall practical purposes straight;

I am aware that tools or mechanisms of this general type are old inthe art, and I' do not therefore claim thesame broadly. I refer to the lathe attachment heretofore patented to I '0. G. Dahlgreu and J. ll. Swenson by Letters Patent of the United States No. 469,813, dated March 1, 1892. This patent, however, expressly states that the sidesof a polygon 5 turned in a lathe equipped with said attachnent will be either concave or convex, and there isno disclosure which would enable oven the most skilled mechanicto construct a tool or mechanism of this general type that would .0 out a polygon the sides of which would be straight, or substantially'so. Thus to cut a substantially straight-sided polygon in this manner formed no part of and was entirely beyond their conception, and theywere oh- ;5 viously ignorant of the elements and conditions necessary to produce such a polygon.

A tool or mechanism embodying my present invention comprises a rotary cutter-having two out ting-points located at on'ehnud'red and e eighty degrees from each other, the axis of said cutter being located at a definite fixed distance from the center of the work and said relative rotary movement to said cutter and work, the angular velocity of the cutter upon its axis beingthree times the relative velocityof said cutter and work.

In .the accompanying drawings a mechan-. ism of my invention is fully-illustrated, said invention being shown as embodied in 'a tool adapted for use in a turret-lathe.

Figure 1 is a top plan view of a portion of a turret-lathe, showing a tool embodying my invention in operative position therein. Fig. 2 is a side view of the parts shown in Fl" 1 Fig. 3 is a sectionalvimv of a tool embodying my invention, taken on the Line 3 3 of Fig. 4,

the hexagon to be out being shown in diagram.

Fig. 4 is a sectional view thereof on the line 4-1 of Fig. 3, and Fig. 5 is a diagrammatic view for the purpose of more conveniently defining certain quantities and dimensions.

I A tool or mech anism'of my invention admits of embodiment in different forms. Among other forms a tool or mechanism of my inven- 35 tion admits of embodiment in a tool adapted for use in a turret-lathe, and for purposes ofillnstration I'have in the drawings shown my improvements as embodied in; a tool of this kind;

Referring now to the drawings, A desig nates as a whole a-tool embodying my 111- vention; B, Figs. 1 and 2, a chuck carried on the spindle of a turret-lathe; B, the turret-- head of the lathe, and 13 a globe-valve secured in said chuck, on t-he'outer end of which the tool A is turning a. regular hexagon, said hexagon being also indicated in diagram in Fi 3.

iii the preferable construction shown the tool A comprises a rigid body portion A, having a shank a, bymeans of which said tool is secured in the turret-head B'of the lathe in ii xed operative position relatively to the work.

- body portion A of the tool.

Revoluhly supported upon the body portion A of the tool, eccentrically to the center thereof, is a cutter A to which a uniform rotary motion upon its own axis is imparted by suitable means. As shown, the cutter A is carried on a shaft or shank A, revolubly mounted in a suitable bearing formed in said Secured to the shaft or shank A, within a recess formed in the body portion A of the tool adapted to re-' ceive it, is a pinion a, which meshes with an internal gear (1*, formed on a ring or collar A, revolubly mounted upon a suitable bearing formed on the body portion A of the tool concentric therewith. It is obvious that rotation of the ring or collar A will impart rotary movement to the shaft or shank A and to the cutter A carried thereon upon the y axis of said shaft or shank. The bearings for the shaft or shank A are preferably hushed. The outside diameter of the bushing a at the front end of said bearing is greater than the diameter of the pinion a, and the outside diametcr of the' bushing a at the rear end of said bearing is less than the diameter of said pinion a at the bottom of the teeth. By this construction provision is made for conveniently assembling said tool, while the rear side of the pinion a will rest in contact with the body portion A of the tool, which'will thus receive the thrust due to the operation of the cutter A all in a desirable manner. The ring or collar A is secured in position upon its bearing by a nut A threaded to the rear end of the body portion A of the tool. To prevent the nut A from binding upon the ring or collar A, said nut is provided with an inwardl y-projectin g flange a, which is adapted'to come into contact with the rear face of thebody portion A of the tool when said nut is in proper position relatively to the said ring or collar.

Any suitablemeans may be used to drive the ring or collar A When possible, how- .ever, I prefer to drive said ring by means of positive connection between said ring and the spindle of the machine. Convenient means for this purpose are as foliows: Rigidly secured to said ring or collar A is an arm a in which is secured a rod a which projects for- 'ward over the work and is ,brought into positive engagement with a rigid arm- 0. on the chuck B by advancing the cutter A toward the work, the relation andadjustment being such that said rod a will be brought into engagement with the arm a before the cutter reaches the work. As shown, the rod a onters a suitable hole in the arm a When driven in this manner, the axis of rotation of the ring or collar A is in .alinement with the axis of rotation of the work. With this construction it is obvious that both the work and 180 sinf the cutter will rotate with uniform angular velocities upon their respective axes.

Whatever its specific form or embodiment may be, a tool or mechanism of my invention comprises certain relative dimensions and movements which are necessarily'constant' in any given case and are calculable from universal formulae. These dimensions and movements are the following: the distance between the axes of the work and of the cutter, the distance from the axis of the cutter to its cutting-goints, and the angular velocity of the cutter upon its own axis relatively. to the relative angular velocity of the work and cutter. I will now give the formulae for deducing these variable dimensions, the expressions used being defined as follows: N the number of sides of the polygon G; n the number of cutting-points of the cutter: 2;

the angular velocity of the cutter upon its own axis relatively to the relative angular velocity of the work and cutter 3; R r the long radius of the polygon-that is, the radius of acircle circumscribed about said polygon; r the short radius of the polygon-that is, the radius of a circle inscribed in said polygon; 'r' the dimension of the cutter from its axis. to its cutting-points; m n the distance between the axes of the work and of the cutter r r, and :0 the angle between a line which bisects the side of the polygon on which the cutter is working, and hence the angle subtended thereby, anda right-line joining the axes of the work and cutter or the angle 1 'm n in Fig. 5 of the drawings. Given the foregoing values and assuming that it is possible to cut a straight-sided hexagon with said tool, then v r (see. as 1) or, more specifically,

It is possible graphically to ascertain very approximately the maximum value of ac-that is, the value of'a; at whichjthe cutter cuts in or out of a given side which will be at an angle of the polygon-and'bysubstituting for a: in the above formula an angle less than said maximum value of m the value of 7" may be derived. It is obvious that if said tool cuts a-straight-sided figure 'r, and hence the formula for the value thereof must be a constant for all values of m less than the maximum value thereof, a trigonometric expression forthe maximum value of m is the following:

7' (see. a: l) cos. 3 so sin. 3 a: tan. of

633,108 I I e -in which equation sin. signifies the angle whose sine is. 13y substituting for a: in formula B for 'r' different values less than the inaximulnvalue thereof 1 find that'r' is constant for all practical purposes, and hence that a tool of this character with the values of r and of m n derived according to said formula B will cut a practically straightsided hexagon. By wayof caution I will say that it is desirableto carry out all trigonometric function and all decimals to six places.

In order to better illustrate the application of the formula in practice, I will now derive the values of -r and of m n necessaryto turn a given hexagon. Assume 1' 1" auda:

substituting in the formula forr,

I 1' see. 8

and m'n a- +1"='1.33458, and substituting in formulaC the maximum value of :r 16. .57.

The cutter is to be setrelatively to the work, as shown inFig. 3 .of the drawings.

I claim-- 1. In atool or mechanism for turning regular polygonal shapes or figures, the combination of a rol-ary cutter of which the dimension 1 cos. a Sill. .1 tan. .1: n -n the axis of said cutter being located eccentrieally to the center'of the shape or figure to be cut and at a distance therefrom equal to r 1*, means to impart relative rotary movement to said cutter and to the shape or figure to be cut and means to rotate said cutter upon its axisgwith a uniform angular velocity relatively to the relative angular movement of 'I' I 1 cos. d a: sin. 5 a: 311.318

the axis of said cutter being located eccentrically to the center of the hexagon to be cut and at a distance therefrom equal to 'r means to impart relative rotary movement to said cutter and to the hexagonal figure to be cut and means. to rot-ate said cutter upon its axis with a. uniform angular .velocity. relatively to the relative angular movement of the hexagon to be cut and the cutter, the angularvelocity oi the hexagon to be cut and the cutter, being to the angular velocity of the cutter upon its axis as one to three, substantially as described.

i. In a tool or mechanism for cutting regu lar polygonal 'figu res, the combination of a re i-ary cutter of which the dimension l. cos. :z Sill. at ..an. I,

the axis of rotalion ol' said cutter being located eccentricullytothc center ol the shape or figure to be cut and at a distance therefrom equal for 'r, means to impart a uniform relative rotary movement to said' cutter and to -the shape or figure to be cut and means to re tate said cutter upon ilsax s with a uniform angular velocity, the angular velocity of the work and cutter being to the angular velocity r i N 'of the cutter upon its axisas one to snbstantially as described. v

4. In a tool or mechanism for cutting regular hexagonal shapes or figures, the combination of a two-pointed, rotary cutter, of which the dimension A '1' (see. a: 1)

' .l cos. 3 .r sin. 3 :1: tan. :1"

the axis of rotation of said cutter being located ecceutrieall y to the center of the hexa gon to be cutandat a distance therefrom or 111911 to r r, means to impart a uniform relative rotary movement to said cutter and tothe hex-, agon to be cut and means to rotate said outter upon its axis with a uniform angular velocity, the angular velocity-of the work and cutter being to the'angular velocity of the cutter upon its axis as one to three, substantially as described.

. 5. In a' tool or mechanism forcutting regular polygonal figures, the combination of a rotary spindle supported in fixed hearings on which the shape or figure to be cut is carried coi'i'centrically with the axis of rotation there of, a" rotary cutter, of which the dimension fr (see. :c-' 1) I- N T cos. :1 $111. tan. an n the axis of rotation of .said cutter, being lo cated ecocntrically to the axis of rotation of the u-ork-carrying spindle and at a distance therefrom equal to r+ r,- meaus to rotate both thework-carrying spindle and the cutter upon their own axes with uniform angular velocities, respectively, the angular velocity of the work-carrying spindle being to the angular velocity of the cutter as one to substantially as described. Y v

G. In atool or mechanism i' or cutting regular hex agons, the combination of a rotary spindie s11 iortod in fixed beariiws on which the the axis of rotation of said cutter being lo- .cated eceentrieally to the axis of rotation of the work-carrying spindle and at a distance therefrom equal to 1' 0'', means to rotate both the work-carrying spindle and the cutter upon their own axes with uniform angular velocities, respectively, the angular velocity of the work-carrying spindle being to the air gular velocity of the cutter as one to three, substantially as described.

7. -In a tool or mechanism for cutting regular polygonal shapes or figures, the combination of a spindle, revolubly supported in fixed hearings, on which the shape or figure to be cut is carried, concentrically with the axis of rotation thereof, a rotary cutter, of which the dimension 'I-(see. .Lv 1) 1 cos. a: sin. a: tan. :1

one to g, substantially as described.

8. In a tool or mechanism for cutting regular hexagons, the combination of a spindle, revolubly supported in fixed hearings, on which the hexagon to be cut is carried concentrically with the axis of rotation thereof, a two-pointed rotarycutter of which the dimension r (see. as 1). 1 cos. 3 msin. 3-a: tan. w

the axis of rotation of said cutter being 10- cated eccentrically to the axis of rotation ofsaid spindle and at a distance therefrom equal to r r, means to rotate said work-carrying spindle and driving connection between-said spindle and cutter whereby rotary movement of said spindle will impart rotary movement to said cutter, the relation of parts being. such that the angular velocity of the spindle will be to the angular velocity of the cutter-as one to three, substantially as described.

9. In a machine for turning regular polygo-' nal shapes or figures, the combination of a spindle, revolubly supported in stationary hearings, on which the shape or figure be out is carried concentrically withthe axis of rotation thereof, a rigid support located opposito to the end of said spindle, a rotary .cuttcr, of which the dimension "1' (see. no 1) 1 cos. a. sin. a: tan. m

mounted in said support so that its axis of rotation is cccentric'to the axis of rotation of the work-carrying spindle and at a distance therefrom equal to 7' -lr and means to rotate both said spindle and cutter with uniform angular velocities, respectively, the angular velocity of the spindle being to the angular velocity of the cutter as one to g, the means for rotating the cutter comprising a band or collar fitted to and revoluble upon'a suitable bearing formed on the cutter-support, a regular internal gearon which meshes witha regular pinion secured to the shank of the cutter, substantially as described.

10. In a machine for turning regular hexagonal shapes, the combination of a spindle, revolubly supportedin stationary hearings, on which the hexagon to be out is carried, concentrieally with the axis of rotation thereof,

a rigid support located oppesite to the end of said spindle, a two-pointed rotary'cutter, of which the dimension 7' (sec. w 1) 1 cos. 3 msin. 3 a: tan, 32"

mounted in said support so that its axis of rotation is eccentric to the axis of rotation of the work-carrying spindle and at a distance therefrom equal to r r and means to rotate both said spindle and cutter with uniform angular velocities, respectively, the angular velocity of the spindle being to the. angular velocity of the cutter as oneto three, the means for rotating the cutter comprising a band or collar fitted to and revoluble upona suitable bearing formed on the cutter-sup-. port, a regular internal gear on which meshes with a regular pinion secured to the shank of the cutter, substantially as described 11. Inamachine for turning regular polygonal shapes or'figures, the combination of a spindle revolubly supported in stationary bearings, on which the shape or figure to be turned is carried concentrically with .the axis of rotation thereof, a rigid supgort located opposite to the end of said spin is, a rotary cutter, of which the dimension E a: tan. m

1 f cos. a:--- sin.

mounted in a suitable bearing in said an port so that its axis of rotation is'eccentr c.

to the axis of rotation of the work-carrying spindle and, at a distance therefrom equal to 1' +1", means to rotate said 5 indle, a -band or collar fitted to and revolub 0 upon a suit!" able bearing formed on said cutter-support,

the spindle is to the angular velocity of the cut-.

ter as one to substantially as described. n

12. In a machine for turning regular hexagonal shapes, the combination of a spindle revolubly mounted in stationary hearings, on

m'ounted in a suitable bearing in said sup port so that its axis of rotation is eccentric to the axis of rotation of the work-carrying spindle and at a distance therefrom equal to 'r 1", means to rotate said spindle, a band or collar fitted toand revoluble upon a suitable bearing formed on said cutter-support, a regular internal gear formed on said band or col- 1ar,whi'ch meshes with a regular pinion secured to the shank of the cutter and an arm on said band or collar which is adapted to be brought into positive engagement with an arm rigidly attached to the work-carrying spindle, the relation of parts being such that the angular velocity of the spindle is to the angular velocity of the cutter as one to three, substantialiy as described.

13. In a turret-lathe, tool for cutting regular polygonal shapes or figures, the combination of a body portion, a shank thereon whereby said tool may be secured in the turret-head, a rotary cutter mounted in a suit: able bearing formed in said bodyportion ot'the tool, of which the dimension a'(sec. w-l)' a .73 flat". I13

aring or collar fitted to and revoluble upon to the spindle of the lathe, and the relation of parts being such that the angular velocity of the spindle will be to that of the cutter as one to i,substantially as described.

It. In a turret-lathe tool for turning regular hexagonal shapes, the combination of a body portion, a shank thereon whereby said tool may be secured'in the turret-head, a twopointed rotary cutter mounted in a suitable bearing formed in said body portion of the tool, of which the dimension 4' (see. :rl)- f 1 cos. 3:1? sin, 3 a; tan. a

a ring or collar fitted to and revo-luble upon a suitable bearing formed on the body port-ion of said tool and which is concentric-with the axis of rotation of the lathe-spindle, when said tool is in operative position and the distance between the center of the bearing of said ring and the axis of said cutter being equal to r r, a regular internal gear formed on said ring orcollar, which meshes with a regular pinion secured to the shank of the cutter and an arm on-said ring which is adapted to be brought into positive engagement with an arm rigidly attached to the lathe-spindle and the relation-of parts being such that the angular velocity of the spindle 'will be to the angular ve ocity of the cutter as one to three. substantially as described I g 15. In a machine forturningpolygoual figures, the combination of a spindle revolubly supported in stationary hearings on which the shape or figure to be cut is carried, a rigid support located opposite to the end of said spindle, a rotary cutter mounted in said support so that its axis of rotation is eccentric to the axis of rotation of the Work-carrying Splfv die and means to rotate both said spindleand cutter upon their own axes, substantially as described. 1

16. In a machine for turning polygonal figures, the combination of a spindle revolubly support-ed in suitable bearings, a support located opposite to the end of said spindle, a

ICC

ures or'shapes, the combination of a spindle revolubly supported in stationary bearings, a support located opposite to th" end of said spindle, a rotary cuttermounted in said support so that its axis of rotation is eccentric tothe axis of rotation of the spindle, means to rotate said spindle and cutter, the means for rotating said cutter comprising a band or collar fitted to and revoluble upon a suitable bearing formed on the cutter-support, an internal gear on which engages with a pinion secured to the shank of the cutter, substantially as described.

v18. In a. machine for turning polygonal shapes or figures, the combination of a spindle revolubly supported in stationary bearings, a

support located opposite to the end of said spindle, a rotary cutter mounted in said support so that its axis of rotation is eccentric to the axis of rotation of said spindle, means to .rotate said spindle, a band or collar fitted to and revoluble upon a suitable bearing formed on said cutter-support, an internal ge'ar on or collar which projects into the path of travel of an arm rigidlyconnected t, t] 13 w or l -earrying spindle, substantially as deseri ed.

19. In a turret-lathe tool, the combination of a body portion, a shank thereon by which said tool maybe secured in the turret-head, a rotary cutter mounted in suitable bearings formed in said body portion of the tool, a ring 15 or collar fitted to and rovoluble upon a suitable bearing formed on the body portion of said tool, an internal gear formed on said ring or collar which engages a pinion on the shank of the cutter, and an arm on said ring or col- :0 lar, substantially as described.

In testimony that I claim the foregoingas my invention Ihave hereunto set my hand this'lith day of October, 1897.

WALTER B; PEARSON.

Witnesses:

LEVI CLARK, BYnoN R- Curran 

